1. Field of the Invention
The present invention relates to a virtual private network (VPN) communication apparatus and method, and more particularly, to an apparatus and method for VPN communication in a socket level that is applicable in an Internet Protocol version 4 (IPv4)/IPv6 complex network.
2. Discussion of Related Art
An Internet Protocol Security Protocol (IPSec) is a security protocol that can be applied to a virtual private network (VPN) communication apparatus. Since the IPSec provides a stable and permanent basis for the security of network layers, the IPSec may be applied in a fire wall, a VPN, and the like. The IPSec may cover not only a standard cryptographic algorithm, but also a new algorithm. The IPSec is essentially provided by an Internet Protocol version 6 (IPv6) protocol, which is called a next generation Internet protocol. However, the VPN communication apparatus using IPSec technology cannot be applied in the mixed IPv4/IPv6 network, since it processes data in a network layer but has no conversion technology between IPv4 and IPv6.
Security Sockets Layer (SSL) technology, which is currently in the spotlight, is a security protocol that provides web security. The SSL technology was developed to provide security and reliability for communications between two applications. However, since the VPN communication apparatus using the SSL technology only covers fixed standard cryptographic algorithms, it may not be used in many applications requiring more security and safety. Also, since the VPN communication apparatus is implemented as software in a client-side, it may frequently conflict with various types of applications.